With development of science and technology, various human-machine interfaces are wildly applied to electronic apparatuses. Touch panels, which are compact in size, easy to operate and more user friendly than other kinds of human-machine interfaces, are more and more popular. Nowadays, the major types of the touch panels include resistive touch panels, capacitive touch panels, electromagnetic touch panels, and optical touch panels, wherein the electromagnetic touch panels should be used with electromagnetic styluses. The electromagnetic styluses include two types, one type is active electromagnetic styluses, and the other type is non-active electromagnetic styluses. Since the active electromagnetic styluses can emit signal, the corresponding electromagnetic touch panels do not need to emit electromagnetic signals, so as to save power.
FIG. 1 is a schematic view of a typical active electromagnetic stylus. Referring to FIG. 1, the typical active electromagnetic stylus 100 includes a tube 110, an electromagnetic signal emitting module 120, a power module 130 and a battery 140. The electromagnetic signal emitting module 120, the power module 130 and the battery 140 are received in the tube 110. The power module 130 transmits power supplied by the battery 140 to the electromagnetic signal emitting module 120 to enable the electromagnetic signal emitting module 120 to emit electromagnetic signals. A corresponding electromagnetic touch panel (not shown) detects the electromagnetic signals and calculates a coordinate location of the active electromagnetic stylus 100 according to the electromagnetic signals. In such manner, the touch control function of the touch panel can be carried out.
However, when the power of the battery 140 is not enough to supply the electromagnetic signal emitting module 120 to emit signal, the battery 140 need to be replaced. This is inconvenient and not environmental friendly.